Tick control bait box use by Peromyscus spp. influenced by habitat placement but raises questions on disease ecology

White-footed mice, Peromyscus leucopus (Rafinesque), and deer mice, Peromyscus maniculatus Gloger, are considered important reservoir hosts for Borrelia burgdorferi sensu stricto, the causative agent of Lyme disease. Host-targeted and nonlethal Select TCS bait boxes have been shown to be effective at killing ticks by delivering small doses of fipronil to wild Peromyscus spp., attracted to the provided bait. This results in reductions in the tick Ixodes scapularis, the vector of Borrelia burgdorferi, in the environment. However, habitat influences on bait box use, interactions with bait boxes, and overall use of bait by small mammals have not been evaluated. These factors may influence the use of this tick control measure. In the current study, bait box use by small mammals was evaluated at five field sites in Maryland, USA, during a two-year study period. Bait consumption in relation to specific described habitats evaluated at each site was recorded, and bait nutrition was compared to nutrition from common northeastern acorn species. Rodent behavior around bait boxes was analyzed using camera traps as well. Bait boxes were used more frequently in herbaceous and shrub habitats than those placed in areas with bare ground or canopy cover alone. Significant amounts of bait were consumed throughout the study, but in some habitat types bait boxes were not used. The bait was found to be similar to native acorns in energy content, suggesting that it may serve as a supplement for natural foods which may have population dynamic implications. Behavioral analysis suggested that Peromyscus spp. foraged around bait boxes regardless of bait presence, but they did not forage in unbaited boxes as frequently. This may suggest the use of odors alone could be enough for attracting rodents to bait boxes potentially reducing the negative effects of baiting while maintaining protective tick control measures.